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by throwaway4496 315 days ago
We process invoices from around the world, so more PDF generators than I care to count. It is hard a problem for sure, but the problem is the rendering, you can't escape that by rastering it, that is rendering.

So it is absurd to pretend you can solve the rendering problem by rendering it into an image instead of a structured format. By rendering it into a raster, now you have 3 problems, parsing the PDF, rendering quality raster, then OCR'ing the raster. It is mind numbingly absurd.
2 comments
troupo 315 days ago
Rendering is a different problem from understanding what's rendered.

If your PDF renders a part of the sentence at the beginning of the document, a part in the middle, and a part at the end, split between multiple sections, it's still rather trivial to render.

To parse and understand that this is the same sentence? A completely different matter.

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throwaway4496 315 days ago
Computers "don't understand" things. They process things, and what you're saying is called layoutinng which is a key part of PDF rendering. I do understand for someone unfamiliar with the internals of file formats, parsing, text shapping, and rendering in general, it all might seem like a blackmagic.
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troupo 315 days ago
No one said it was as black magic. In the context of OCR and parsing PDFs to convert them to structured data and/or text, rendering is a completely different task from text extraction.

As people have pointed out many times in the discussion: https://news.ycombinator.com/item?id=44783004, https://news.ycombinator.com/item?id=44782930, https://news.ycombinator.com/item?id=44789733 etc.

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throwaway4496 315 days ago
You're wrong. There is nothing inherent in "rendering" that means "raster or pixels". You can render PDFs or any format into any format you want, including XML for example.

In fact, in majority of PDFs, a large part of rendering has to do with composing text.

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nottorp 315 days ago
You are using the Mark 1 eyeball for each new type of invoice to figure out what field goes where, right?
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throwaway4496 315 days ago
It is a bit more involved, we have a rule engine that is fine tuned over time and works on most of invoices, there is also an experimental AI based engine that we are running in parallel but the rule based Engine still wins on old invoices.
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